Railway-signal.



PATENTBD APR. 25, 1905.l

Am 7. 6 91 7 8 7 nw N RAILWAY SIGNAL.

APPLICATION FILED H1B. s. 1905.

Patented April 25, 1905 ASBURY G. WILSON, OF WILIUNSBURG, PENNSYLVANIA, ASSIGNOR TO THE UNION SVITOH AND SIGNAL COMPANY, OF

SWlSSV-ALE, PENN- SYLVANIA, A CORPORATION OF PENNSYLVANIA.

RAlLwAY-SIGNAL.

SPECIFICATION fOrmiIig part f Letters Patent N 0. 787,967, dated April 25, 1905.

y Application filed February 3,1905. Serial No. 243,965.

To all whom, it mng/ concern:

Beit known that l, AsnURY G. WILSON, a citizen of the United States, residing at filkinsburg, in the county of A llegheny and State of Pennsylvania, have invented certain new and useful' Improvements in Railway-aignals, of which the following is a specilication. This invention relates to apparatus for operating railway-signals, and particularly to that class of railway-signals in which the motive power therefor is in the form of fluidpressnre. In railway-signals of this character the signal is moved inone direction by the fluid-pressure and in the other direction by I5 gravity. The fluid-pressure apparatus usually comprises a motor in the form of a cylinder and piston and valves for controlling the admission of the fluid to and its exhaust from the cylinder. The piston is usually connected to the counterweight of a semaphoresignal, and when heavy semaphore-castings are employed the return of the piston under the influence of the counter-weight frequently subjects the apparatus to a severe shock, and

the prevention of such shocks is the object of the present invention.

l will describe au apparatus for operating; railway-signals embodying my invention and then point o'ut the novel features thereof in claims.

ln the accompanying drawings l have illustrated so much of the operating mechanism of a railway-signal as is suicicnt to illustrate the application thereto of my present invention.

In such drawings, Figure l is a vertical section of part of a signal-operating apparatus. Figs. 2 and 3 are sectional views, on an enlarged scale, showing my present invention.

Figs.4 and 5 are respectively side and end views of a plug containing' a check-valve.

Similar letters of reference designatecorrespending parts in all of the figures.

By the term fluid-pressure i mean a liquid or gas under pressure, and preferably I employagaswas, for example, air or carbonicacid gas-and under any pressure which is sufhcient or more than sutcient to operate the apparatus or mechanism for moving the signal. There the pressure is above that required, reducing -valves may be employed wherever desired.

Referring now to the drawings, (l designates a piston, and rl a cylinder within which the piston moves. The piston, it is 'to be understood, will be connected in any suitable manner to a semaphore-signal, (not shown,) it being deemed not necessary to illustrate the signal nor the connection of the piston thereto, it being well known to those lskilled in the art that the piston Z will be moved upwardly by the fluid pressure and downwardly by gravity when the fluid-pressure is released.

The fluid-pressure passes from a source of supply (not shown) through a -pipe a to a chamber containing a valve 12, which is normally held in a closed position, but may be opened by an electric device 1)' in the manner described in United States Patent No. 745,309, granted November 24, 1903, to J. .(,oleman` and which need not be particularly described herein. W'hen the electric device D' operates to open the valve di, it will also close the valve d", and thereby close the exhaust-passage e. It will be observed that the cylinder-heini l) is provided with a boss d", which is bored out and internallythreaded to receive the cxteriorly-thrcaded plug F, provided with a reduced end portion f and a longitudinal passagef", which is made flaring at its outer end to receive the tapered portion r/ of the casing containing the valve (Z2, such casing having also a passage g, which connnunicates with the passage f' in the plug F. The reduced inner end of the plug F is tubular -and provided with a valve-seat j. upon which the loose freely-movable check-valve f3 is adapted to seat. 'lhe stem f* of the valve is of less diameter than the passage f', into which it extends and serves to guide the valve. In order to limit the movement of the valve f3 away'from its seat, a pin f is secured in the reduced end of the plug. 'hen the plug F is in place, an annular chamber fu iswformed around the inner end of the plug and a passage f7 is formed in the plug which leads from A back f ancith'e chaini the valve. From the chamber-f a passage leads to other die said chamber-to the passage the valve, and this na her f i" rm a by-pass aroi. el.

passages if andv (Z5, the latter et which com- Such being a preferred embodiment of my invention its operation is as follows: When the electric device D' is energized to open the valve Z2 and simultaneously close the valve nl, the iluid-iiressurc will pass around the valve d into the passage q, thence into the passage f. past the valvcfa, and also through the passage f7 into the annular chamber f5' through passages r/Z and d to the cylinder ft below the piston (l, and it will be observed by reference to Fig. 3 that the valve fdoes notoiier any obstruction to the flow of fluid-pressure to the cylinder. Vilien, however, tlhe valve if is closed and the valve d3 is open and the piston (Z begins to descend under the inllueiice of the heavy counterweight on the signal, the valve 'f3 will be forced to its seat, as in Fig. and the only escape for the `fluid-pressure will be throughithe passage f7, wliizh being restricted will retard the escape of such -iluid-pressure, and thereby cause the latter to forni cushion below the piston, and thus pre-vent shocks to the apparatus.-

lllor details of construction and the operation ot the remainder ot' the apparatus illustratt-d reference may he had to United States iatent if i. T- hercinbei'oi'e referred to.

'l' invention is applicable to any and all furnis olA raiMay-signals eiiiploving a piston :and cylinder to nieve the semaphore or other ijna. devices an( llii"l-prf.issiire to cause a nient olA Hi i piston in ihe cylinder. claim l, in apparatus for opera' ing railway-s g mais.. the lnibination with' -tiuid-pressure from a source of supply to the cylinder`- below the piston, inlet and exhaust .valves in said conduit, a check-valve in said conduit between the cylinder and the inlet.

and exhaust valves, and a byepass from said 'cond-nit around the cheek-valve.

duit between the cylinder and the inlet and exhaust valves, and a by-pass r'roiii said conduit around the check-valve.

4. le apparatus for operating railway-signals, the combination with a cylinder and a piston therein, of a plug fitted in the cylinderhead and having a tubular inner end portion provided with a valve-seat, a checkvalve loosely supported within said tubular end portion. the said head halving an annular chamber surrounding the inner end of the plug and a passage leading therefrom to the cylinder helow the pistoni, and said plug having a longitudinal passage and a branch passage leading therefrom in rear ot' check-valve to said arinulai' chamber, and means for conveying fluidpressure to or from the central passage in the plug.

5. In apparatus for operating railway-signals, the combination with aEcylinder anda piston therein, oi' a plug iitted'in the cylinderhead and having areduced, tubular, inner end portion provided with a valve-seat and/a longitudinal passage leading from said valveseat to the outer end oi' the plug, a check-valve loosely supported within tl'ie tubular end por? i the said annularchamber to the said longitudiiial passage in rear of the check-valve. and

, cylinder and a i ein, ol' a conduit ior conveyingsure i'i-oiii a source ei supply to the i cylinder helen' the piston, a check-valve in 'l said i'i,=iiduit, and a h v-pass troni said conduit l around the cheek-valve.

piston therein, oiLA a conduit for conveyingl valve-controlled means for delivering nuid- IOO pressure to and exhausting it from. said lon-"y gitiiilinal passage.

in testimony whereofl have signed iiiy name to this specification iii 'the presence of two suhscrihed witnesses. v

ASBURY (l. Wl LSON, ll'itnesses:

M.. I). HANLoN, W. L. MCDANIEL. 

